Moscow's Metro is one of the most-used underground railways in the world, carrying about 5.5 million passengers a day.

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They also enjoy a continuing monopoly over construction and civil engineering projects, from dams to bridges, and highways to metropolitan underground light railways.

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If only the buses, underground systems and railways worked cheaply and efficiently, then motorists would leave their cars at home.

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Tube trains and railways ground to a halt, trapping thousands of people underground and stranding tens of thousands more on rainy platforms.

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